Structure and Polarity of 1,4-Dimethoxybenzene

Structure

The chemical structure of a molecule includes the arrangement of atoms and the chemical bonds that hold the atoms together. The 1,4-Dimethoxybenzene molecule contains a total of 20 bond(s). There are 10 non-H bond(s), 6 multiple bond(s), 2 rotatable bond(s), 6 aromatic bond(s), 1 six-membered ring(s), and 2 ether(s) (aromatic). Images of the chemical structure of 1,4-Dimethoxybenzene are given below: 

Polarity and Molecular Orbital Study

The polarity of the molecule is determined by its structure. The structure of 1,4-Dimethoxybenzene consists of a benzene ring and two para-position methoxy groups. Therefore it behaves as a non-polar molecule.

The conformational equilibrium in 1,4-dimethoxybenzene (1,4-DMB) in benzene solutions has been studied by Maria Dutkiewicz and Jerzy Małecki^[1]. On the basis of experimental values of the nonlinear dielectric effect (NDE) parameter, electric permittivity and density, determined in this work, and applying the general statistical theory of NDE, the contributions of the syn-anti and syn-syn conformers and the electric dipole moment of the polar syn-syn conformer were calculated. The molecular orbital method (PM3) has also been applied for calculation of the dipole moments and energies of particular conformers. The results of the NDE study and PM3 calculations are consistent and they reveal the existence of two conformers (syn-anti and syn-syn) of comparable energy values, but different values of dipole moments, and the predominance of the polar form (syn-syn) of the mole fraction in benzene. Moreover, the energies of intermolecular interactions have been determined from the concentration dependence of linear and nonlinear polarisability.

Reference

[1] Nonlinear dielectric effect (NDE) and molecular orbital study of the conformational equilibrium in 1,4-dimethoxybenzene in benzene solution. doi:10.1016/S0022-2860(97)00049-5